Avaliação do impacto da amostragem, proporção massa/solvente e equipamento de extração na análise de pesticidas em alimentos

Abstract

This study aimed to investigate the applicability of miniaturization of conventional analytical methods for the analysis of pesticide residues in foods. With the growing demand for faster, more cost-effective, and environmentally sustainable analytical methods, there is a need to improve the procedures used for pesticide residue analysis. In classical methods employed by the agrochemical industry and private laboratories, the use of advanced instrumental techniques for separation, detection, and quantification of analytes contrasts with the tedious, time consuming and manual methods used for sample preparation, which can delay and increase the cost of the entire analytical process. Therefore, this research project investigated how different variables employed during the extraction of pesticide residues in foods can influence the levels of residues found in these samples, with the aim of automating the analytical methods. For this purpose, results of six active ingredients (mefentrifluconazole, pyraclostrobin, fluxapyroxad, teflubenzuron, boscalid, and dimoxystrobin) were evaluated in four different matrices (tomato, citrus, cotton, and rice). A full factorial design (23) was utilized, considering the extraction techniques (Ultra Turrax and vortex mixer), sample mass (0.20 g and 2.50 g), and mass/sample volume ratio (1:8 and 1:20). The results obtained indicated that, even with small sample masses, comparable standard deviations were achieved compared to conventional methods. Furthermore, the mass/sample volume ratio showed low significance in the variation of results for the tested levels. Although some variables, such as sample mass and equipment, presented significant effects, these effects were within the expected variability for pesticide analyses. Additional experiments were performed to validate the applicability of miniaturization and automation of the analytical methods.